1. Field of the Invention
The present invention relates to an improved cleaning unit of a broad width industrial-use electrostatic process copying apparatus, and more particularly, to a mechanism for reasonably loading and unloading the cleaning unit and the main charger into and from an industrial-use electrostatic process copying apparatus.
2. Description of the Prior Art
FIGS. 18 and 19 respectively show lateral views of such an industrial-use electrostatic process copying apparatus. Of these, FIG. 18 is the simplified lateral view. FIG. 19 is the lateral view denoting a condition in which a part of the copying apparatus is opened to allow an operator to perform maintenance and inspection of a cleaning unit.
When operating this conventional copying apparatus 1, a document is conveyed by the document feeding rollers 2a and 2b A document image radiated by a light source 3 passes through a lens array 4 and is made on the surface of photoreceptive drum 5. The surface of the photoreceptive drum 5 is uniformly charged with positive load by the main charger 6. Light corresponding to the document image passing through the lens array 4 radiates positive charge. Then, charge disappears from this portion to generate a static latent image. When the portion formed static latent image passes through developing device 7 by rotation of photoreceptive drum 5, toner adheres to static latent image and eventually forms toner image.
On the other hand, copying paper placed on paper-feeding tray 8 is delivered to feed roller 11 through paper-feed roller 9 and resist roller 10. Toner image formed on the surface of photoreceptive drum 5 is transferred to copying paper while the copying paper passes through transfer device 13 between photoreceptive drum 5 and transfer charger 12.
Copying paper bearing toner image then passes through fixing device 14 so that toner image can be fixed. Then, copying paper is transferred to paper-discharge tray 16a via paper-discharge roller 15.
Resist roller 10 is composed of the upper resist roller 10a and the lower resist roller 10b. Feed roller 11 is composed of the upper feed roller 11a and the lower feed roller 11b.
Cleaning unit 16 is installed to a position close to external surface of photoreceptive drum 5 for cleaning it by scraping off residual toner from external surface of photoreceptive drum 5.
Cleaning unit 16 and main charge 6 are independently installed to the conventional industrial-use copying apparatus 1 described above. As a result, in order to perform maintenance and inspection of cleaning unit 16 and main charger 6, copying apparatus is divided into two parts, i.e., stationary part la and movable part lb, as indicated by dotted line 17. Movable part lb can be moved to the position indicated by two-dot chained line of FIG. 19. When movable part 1b moves, both the cleaning unit 16 and main charger 6 are externally exposed for removal outside of copying apparatus.
Namely, paper-discharge tray 16a, paper-discharge roller 15 and transfer device 13 are provided on the movable part 1b. Additionally, parts of elements of the paper-conveying path (a part of a body of copying apparatus) being composed of lower feed roller 11b, transfer charger 12, upper resist roller 10a and the like are provided on said movable part 1b. Opening 18 is formed by transferring the movable part 1b at a right angle to the axis of photoreceptive drum 5, and thus, cleaning unit 16 can be extracted in the direction of the arrow 19. Main charger 6 can also be extracted in the arrowed direction 20.
As mentioned above, on any conventional industrial-use copying apparatus, opening 18 is generated by slidably moving of the movable part 1b which constitutes a part of the body of the coping apparatus. Since either cleaning unit 16 or main charger 6 must discretely be taken out of opening 18 or loaded into copying apparatus through opening 18, operator is obliged to execute double handling operations.
Furthermore, as shown in FIG. 19, since main charger 6 is installed to a specific position hardly discernible from opening 18, operator is obliged to blindly install lengthy main charger 6 to a specific position close to photoreceptive drum 5. This is a major setback, which may cause damage to photoreceptive element on the surface of photoreceptive drum 5.